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Unread 05-04-2012, 19:35
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icyplanetnhc icyplanetnhc is offline
The infamous Haoch
AKA: Haochuan
FRC #0846 (The Funky Monkeys)
Team Role: Alumni
 
Join Date: Jun 2010
Rookie Year: 2009
Location: San Jose, California
Posts: 7
icyplanetnhc is an unknown quantity at this point
Re: Moment of inertia and turning performance

Quote:
Originally Posted by Al Skierkiewicz View Post
Haochuan,
The "jumpiness" that teams describe is primarily the torque of your drive train overcoming friction with the floor. As a wheel breaks loose and the RPM jumps up, the result is a mini-wheelie when the tires again grab the carpet. In most cases with high friction tires (four or more wheels) this is the case when turning.
We hypothesized that the jumpiness of our turning is caused by the inherent rocking of the standard West Coast 6WD drivetrains. This rocking causes inconsistent resisting torque to the turning. Each time the robot rocks during a turn, the front or rear wheels would grab the carpet, creating an abrupt but sharp resisting torque to our turning before the robot begins rocking the other way. Each rock seems to amplify the jumpiness and bounce.

However, we noted that some teams are able to create very smooth 6WD drivetrains that are similar in configuration to ours (254's Slipstream, for example). We will analyze some high-speed footage to get a better understanding of why we are suffering from this problem.
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"Do the math, save the world." - Mark Leon
FRC #846 -- 2009-2011